Patent GB-276444-A (GB)
Title: Improvements in or relating to the heating of machine tools
IPC: C14B1/00
Filed: 1926-05-29
Abstract: 276,444. British United Shoe Machinery Co., Ltd., Ricks, F., and Richards, A. E. May 29, 1926. Sheet material, finishing edges of. - In machines for operating progressively upon the edges of sheet materials such as leather, and having work-feeding means and a heated operating-tool, and means for heating the tool tn different temperatures, a single-member control arrangement is provided, movement of which by the operator can vary the rate of the work feed and the heat of the tool conjointly, and, at a given feed rate, varies the heat of the tool only. The invention is described in connection with the work-feed control employed in Specification 234,170. A shaft 2 controlled by a treadle 1 is pivoted in a fixed bracket 3 and is secured to an arm 4 pivotally connected to a rod 5, the upper end of which is pivotally connected to one end of a lever 6 mounted in a bracket 8 on the underside of the work bench 9. The other end of the lever 6 is forked to form end bearings from a shaft 10 provided with a hole through which extends a slidable pin 11. The pin 11 is surrounded by a helical spring 13 disposed between a fixed collar 15 and the top of the fork, a collar 16 being provided on the lower end of the rod to limit its upward movement. The pin 11 slides within a block 17 and co-operates with a rod 79 controlling the work-feed mechanism, the action being such that the lifting of the rod 79 by the rod 11, consequent upon the depression of the treadle, increases the rate of feed. The treadle is mormally held raised by a spring, the ends of the rods 11, 79 then being separated slightly. An arm 18 secured to the treadle shaft 2 is pivotally connected to a rod 19, which is adjustably secured to a member 20 connected to the plunger 21 of a choke coil 22 through which an electric current passes to the searing tool of the machine, the depression of the treadle acting to withdraw the plunger and increase the heating current. The heat of the tool may be indicated on a scale 24 by a pointer 26 on a rod 25 connected by a pivoted arm 27 and rod 30 to the plunger 21. On the initial depression of the treadle the lost motion between the rods 11, 79 allows the heat of the tool to be increased before the work feed is increased, the rods subsequently coming into contact and increasing the temperature and feed rate concurrently. An adjustable stop may be provided to arrest the rods 11, 79, to prevent further increase of the feed rate, but the spring 13 allows the treadle to be depressed further to increase the heat of the tool. A stop 31 may be provided to limit the movement of the treadle to prevent overheating of the searing table. The ratio between the increase of temperature and increase of feed rate may be varied by providing a series of holes 32 in the arm 4 to receive the lower end of the rod 5. In a modification, Fig. 2, the lower ends of the rods 5, 19 are respectively connected to the arms 45, 46 of a yoked member pivoted on a shaft 41 and controlled by either or both feet acting upon two treadles 42, 43, which are pivoted on the shaft 41 and extend above the two ends of a lever 49 pivoted within a lug 47 on the arm 46. Specification 26300/12 also is referred to.